It is the aim of this project to establish general routes for the total synthesis of some tumor inhibitory hydroazulene sesquiterpene lactones. Specifically, we are attempting to synthesize guaiol, damsin, and psilostachyin. The routes used will involve some new chemistry which we are developing. We have, for example developed several new methods of ring expansion to allow construction of the necessary cycloheptane rings present in the natural products. We have also developed a new method for the synthesis of alpha- methylenebutyrolactones which we hope to make use of. In addition to the synthetic goals which we hope to attain, it is a further aim of this project to study the stereoselectivity of reactions in the hxdro-azulene system. We hope thereby to develop general rules governing hydroazulene stereochemistry much the same as rules have been developed for the decalin system.